Jason Duling – Sales – 2M CCTV

877-926-2288 x 6053

I occasionally get the phone call inquiring about CCTV lux and how it relates to video surveillance cameras. My personal favorite goes something like the following:

Yeah, I’m on your website looking at cameras and am looking for a camera with around 0.3 lux. Can you help me?

My inside voice asks: .3 lux? Could you explain to me in laymen’s terms exactly what that means? Better yet, could you send me the mathematical formula that you used to determine that exact rating for your particular application?!

Fortunately, my outside voice usually jumps in and says: I would be happy to help you with that! (dumb outside voice :)). For time’s sake (nerds and engineers please conduct online search of illuminance, luminous emittance, or photometry, etc), LUX rating is nothing more than a measure of the total amount of visible light present. The lower a camera’s lux, the lower the amount of light needed to get a good picture. For instance:

- 1.0 lux will suffice for an application where a sufficient amount of light is available.

- 0.00001 lux is perfect for extremely low light applications (like the back of a cave or under a bucket).

Here is a CCTV lux rating chart to demonstrate the lux required in a surveillance camera for a particular outdoor lighting condition.

CCTV LUX Chart for Different Lighting Conditions

The above chart is for outdoor lighting conditions (see our outdoor surveillance cameras), but can easily be used to determine the lux needed for indoor use. For instance, 10.75 lux is ideal for inside your home (see our selection of home security cameras) and 107.53 lux would be used in office lighting.

Note: Don’t be confused with the foot candles in the chart, it’s a unit used more in the lighting industry (museum, gallery fields, etc.) than the surveillance industry. But in case you are a fan of math, one footcandle = 10.764 lux

Rule of thumb, if an application includes an area with very little or no light source, select a camera with IR leds. These will allow you to view in even the darkest of situations as the camera supplies its own infrared (IR) light and has a cctv lux rating of 0.000 (no light required).

If all else fails give me call and describe your cctv application to me. I promise to use only my outside voice while helping to design the very best solution for your needs, enabling you to capture the images you desire in any and all lighting situations.

Good day! This is my 1st comment here so I just wanted
to give a quick shout out and say I truly enjoy
reading your blog posts. Can you suggest any other blogs/websites/forums that deal with the same topics?

Does it mean in an extreme dark night with dark rain clouds looming in the sky, the IR camera”s ir lights willnot come on and give image to the camera?please explain knowledgeable people as I am shopping for an ir ip cam with 0.5 lux

Now i really know that some footage or an output of surveillance CCTV cameras goes into different range of LUX mentioned. I mean if someone liked/wanted to own a clear and better picture for an image to appeared with clear resolution of the footage, the camera must be set into an exact range of LUX.

This is a good reference for people installing spy cameras for home as they often expect too much from the camera at night.
It would be good to extend on this and discuss the relationship between f-stop and lux in the cameras performance as this is where many budget cameras mislead people.
They state something like minimum illumination 0.1 lux @ f1.2 but actually supply the camera with a f2.0 lens.

Hi Jason,
You’re not alone… I also do not know the meaning of LUX…
Maybe I should ask more details if purchase of CCTV. You explain it well… Where did you get this chart?
Are all LUX can be used for home security system?

Well written Jason.
Isn’t if frustrating when the person looks in the local electronics shop and sees the cameras marketed as 0 lux. They are typically a dome or bullet camera with 6-10 IR leds around the lens and give a terrible image, with a huge hot spot of light, making the image next to useless.
I wrote an article on this topic as part of my CCTV training at CCTVdesign.com.au